Sadly there is not much than can be done, although the bitch will probably be fine. My main worry (apart from the bitch being physically immature) is that she may not know how to cope with the puppies, so they should watch that she is feeding and cleaning them properly. Tell them to get as much good food into her as possible, to help her to build up some reserves for her and the puppies, and so she will be able to produce enough milk for them.
If you think about it, this is what would probably have happened in the wild, and although defnitely not ideal, I am sure she will be ok.